The present invention relates to a sealed type rotary compressor including an electromotive element and a rotary compression element in a sealed container. More particularly, it relates to a sealed type rotary compressor in which a rotary compression element is received in the lower part of a sealed container and in which an electromotive element is received above this rotary compression element, the electromotive element being constituted of a stator, and a rotor rotatably inserted into a magnetic field generated by this stator and fixed to a rotary shaft which also serves as a crank shaft to drive the rotary compression element.
Heretofore, this type of sealed type rotary compressor is constituted of a rotary compression element received in the lower part of a sealed container and an electromotive element received above the rotary compression element. The electromotive element is constituted of a ring-shaped stator attached along the inner peripheral-surface of the upper space of the sealed container, and a rotor rotatably inserted into a magnetic field generated by this stator and fixed to a rotary shaft which also serves as a crank shaft to drive the rotary compression element.
The rotary compression element is constituted of a cylinder, a roller fitted into an eccentric portion formed in the rotary shaft to eccentrically rotate in the cylinder, and a vane which abuts on the cylinder to divide the inside of the cylinder into a low pressure chamber side and a high pressure chamber side. Moreover, in the bottom part of the sealed container, oil for lubricating sliding portions such as the rotary compression element and the rotary shaft is stored.
Moreover, when a stator winding of the stator of the electromotive element is electrically energized to generate a rotation magnetic field, the rotor provided in this magnetic field rotates. By this rotation, the roller fitted into the eccentric portion of the rotary shaft eccentrically rotates in the cylinder. In consequence, a low pressure refrigerant is sucked on the low pressure chamber side in the cylinder, and compressed by the operations of the roller and the vane. The refrigerant gas compressed in this cylinder to have a high temperature and a high pressure is discharged from the high pressure chamber side to a discharge muffler through a discharge port. The refrigerant gas discharged to the discharge muffler is discharged into the sealed container through discharge hole which connect the discharge muffler to the sealed container and which are directed upwardly to the electromotive element. At this time, the oil supplied to the rotary compression element and having a mist state is mixed in the refrigerant gas, and the oil is discharged together with the refrigerant gas into the sealed container.
The refrigerant gas discharged into the sealed container passes through a refrigerant passage formed in the electromotive element and is discharged to the outside of a discharge pipe provided above the electromotive element (see e.g., JP-A-9-151885).
However, in such a conventional sealed type rotary compressor, the refrigerant gas and the oil cannot sufficiently be separated in the sealed container, and the amount of the oil discharged through the discharge pipe is large, which causes problems that performance deteriorates owing to the outflow of the oil to an external circuit and that the oil supplied to the sliding portions runs short.
The present invention has been developed to solve such problems of the conventional technology, and an object thereof is to promote oil separation in the sealed container, thereby decreasing the amount of the oil discharged to the outside of the compressor.